Here's what I do, basically exactly what lunger just explained ^^^^
The same reason why I do this is to keep it 100% viewable through the front tank. I don't dig the screen on top or bottom of look. I have a couple tanks like that and I'll never go back. Drill some holes and buy grommets like lunger explained. Total clear front view and there's really not ever any condensation. I have some small tanks that have fans running a few times to clear it up but honestly I'd be fine without the fans. I just had them laying around.
Here's some pics. Hope it helps. ImageUploadedByTapatalk1434891847.168040.jpgImageUploadedByTapatalk1434891860.485605.jpg

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